Recently I was working on a project in which a country road had a small drainage ditch to the side of it with flowing water in it. I looked at it once, and instantly thought, “I need to add a sound for that!”
Two weeks later, I was taking a hike through Cougar Mountain Regional Park (didn’t see any cougars– feline or otherwise), when I came across a very similar scenario in real life: a small stream of water flowing downhill. I stopped, looked, and listened, but to my surprise I heard no water trickling or babbling sounds emanating from this little stream.
If I went back and removed the sound from my project, someone could walk through the world, see that ditch, and wonder, “why the hell isn’t there a water flowing sound coming from that water?” The simple point here is that our perception of sound often differs from the reality of sound, and in games (or any form of media for that matter) we need to carefully weigh this when crafting an aural landscape. If a user is expecting a sound and it’s not there, it makes a negative impression. Not necessarily because the overall sound design is bad, but rather s/he notices a sound is missing. We have broken the wall of immersion. In the real world, slow moving water needs speed, but it also needs an obstruction in its path to cause enough movement to generate an audible sound. In the game world; however, it may just need to exist with the illusion of movement: perhaps it’s just an animated texture, or a shader trick. There doesn’t need to be a rock or an eddy causing a rapid, it’s just there, it’s expected, so let it have sound. Unless of course that goes against the aesthetic you’re trying to develop in the course of your project.
Sound design is all about managing perceptual expectation. We all know how weak gunfire sounds in real life compared to that which we create for games and film. So there is both the need to manage perception in the design of individual sounds as well as on the implementation side of sound design. But how do we choose what aspects in the world should and should not have sound and how those sounds behave? There are two things to consider here: technical and aesthetic.
On the technical side there are decisions to make based on what is available to you. What device(s) are you developing for? How much memory do you have available? Do you have DSP? Is there any sort of scripting or complex behavioral structure at your disposal? How many concurrent sounds can we play? What else may be concurrently going on in the world? Fortunately, as technology evolves, tools and technical specs are both improving so that even mobile games can use Wwise, FMOD, Unreal, etc. to provide the designer with more options, power, creativity, and flexibility to achieve their sonic goals for a project. Handhelds and mobile are losing their “stripped down,” “less powerful” monikers so that the only limitations we may have on our sound design are those we choose to put there. Of course, we’re not to the Mecca of no technical restrictions yet. Even on Playstation 4, I don’t have limitless memory and resources and that’s probably a good thing. Limitations often drive creativity and allow you to see things in a different light. We still need to fit our design into the technology we’re using, it’s just a matter of understanding the limitations of that tech and working through them.
The aesthetic side is more of a gray area. Technical specs are often set in stone, and while you may be able to negotiate for extra resources, you’re still working in an established ballfield. When determining what should have sound and how it should sound, that’s where the creative and artistic part of sound design really kicks in. This is where you get to decide (either by yourself is sometimes with the assistance of a game/creative director or other audio personnel) where you want the audio to take the user and how it should make them feel. There’s no real science in determining what is right or wrong, it’s usually a mix of gut feeling, experience, and inspiration from others that can drive you to the right place creatively.
I do not mean to suggest that technical and aesthetic design decisions are mutually exclusive. On the contrary, in a well designed audio plan, they are intimately entwined, each one informing the other. We generally want to create a believable soundscape within the context of the game world. What that means specifically is part of the beauty and mystery that is our craft. And the key to meaningful sound design is often understanding the differences in perception and reality and ensuring your audio vision for a project matches the sonic landscape you wish to create.